Quantitative Lipidomics Analysis of Zebrafish

The extracted total lipids from zebrafish’s tissues were dried under nitrogen gas and re-dissolved in 400 μl of acetonitrile/2-propanol/H₂O (65:30:5) immediately. The samples were analyzed by LC/MS Ion-Trap (Bruker Corporation). A total of 50 μl dissolved sample was injected through the autosampler. HPLC mobile phases contained solution A: ACN:H₂O (60:40), 10 mM ammonium formate, 0.1% formic acid and solution B: IPA:ACN (90:10), 10 mM ammonium formate, 0.1% formic acid[34 (link)]. Gradient was from 60% solution A to 100% solution B in 25 min and maintained 100% solution B until 45 min in an Acclaim RSLC 120 C18 2.1 mm x 100 mm 2.2 μm column (Thermo) at a flow rate of 0.2 mL/min at 55 °C. Data were further analyzed by Bruker DataAnalysis (ver.4.1). The extract ion current (XIC) of each cardiolipin species was quantitated by their relativity of XIC to internal standard. Standard curve of XIC detector response versus content of cardiolipin standard is provided in S1 Fig.